U.S. patent application number 16/321537 was filed with the patent office on 2019-06-06 for insulative apparatus.
This patent application is currently assigned to Dow Global Technologies LLC. The applicant listed for this patent is Dow Global Technologies LLC. Invention is credited to Ning Chai, Cheng Chen, Jing Chen, Vanni Parenti, Yige Yin.
Application Number | 20190169393 16/321537 |
Document ID | / |
Family ID | 61015425 |
Filed Date | 2019-06-06 |
![](/patent/app/20190169393/US20190169393A1-20190606-P00899.png)
United States Patent
Application |
20190169393 |
Kind Code |
A1 |
Chai; Ning ; et al. |
June 6, 2019 |
INSULATIVE APPARATUS
Abstract
Provided are insulative apparatus and methods of forming
insulative apparatus. As an example, a method of forming an
insulative apparatus can include connecting a barrier material to a
mold; injecting a polyurethane foam composition into the mold,
wherein the polyurethane foam composition includes a polyol, an
isocyanate, and supercritical carbon dioxide; curing the
polyurethane foam composition to form a polyurethane foam and
applying a vacuum to the mold to provide a pressure from 1 millibar
to 500 millibar.
Inventors: |
Chai; Ning; (San Ramon,
CA) ; Chen; Jing; (Shanghai, CN) ; Yin;
Yige; (Shanghai, CN) ; Chen; Cheng; (Shanghai,
CN) ; Parenti; Vanni; (Campagnola Emilia,
IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Dow Global Technologies LLC |
Midland |
MI |
US |
|
|
Assignee: |
Dow Global Technologies LLC
Midland
MI
|
Family ID: |
61015425 |
Appl. No.: |
16/321537 |
Filed: |
July 29, 2016 |
PCT Filed: |
July 29, 2016 |
PCT NO: |
PCT/CN2016/092186 |
371 Date: |
January 29, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29C 44/065 20130101;
C08G 18/1808 20130101; C08J 2205/044 20130101; B29C 44/1209
20130101; C08J 2205/05 20130101; C08G 18/1816 20130101; C08G
18/7664 20130101; C08G 2101/0025 20130101; C08G 2330/50 20130101;
F16L 59/00 20130101; C08G 18/092 20130101; B29C 44/14 20130101;
C08G 18/2036 20130101; C08J 2375/04 20130101; C08G 2105/02
20130101; C08G 18/4816 20130101; C08G 18/4829 20130101; C08J 9/122
20130101; C08J 2203/08 20130101; C08J 2203/06 20130101 |
International
Class: |
C08J 9/12 20060101
C08J009/12; C08G 18/18 20060101 C08G018/18; C08G 18/76 20060101
C08G018/76 |
Claims
1. A method of forming an insulative apparatus, comprising:
connecting a barrier material to a mold; injecting a polyurethane
foam composition into the mold, wherein the polyurethane foam
composition includes a polyol, an isocyanate, and supercritical
carbon dioxide; curing the polyurethane foam composition to form a
polyurethane foam; and applying a vacuum to the mold to provide a
pressure from 1 millibar to 500 millibar.
2. The method of claim 1, wherein the polyurethane foam has an
average pore diameter from 2 microns to 100 microns.
3. The method of claim 1, wherein the polyurethane foam has an open
cell percentage of 95% or greater.
4. The method of claim 1, wherein the polyurethane foam has a
porosity from 80% to 98%.
5. The method of claim 1, wherein the polyol comprises a formulated
polyol.
6. The method of claim 1, wherein the isocyanate comprises
isocyanic acid polymethylenepolyphenylene ester.
7. The method of claim 1, wherein the barrier material has an
oxygen transmission rate from 1e-20 m.sup.3 m/(m.sup.2 Pa day) to
1e-12_m.sup.3 m/(m.sup.2 Pa day).
8. The method of claim 1, further comprising combining the polyol,
the isocyanate, and the supercritical carbon dioxide in a pressure
vessel.
9. The method of claim 7, wherein the pressure vessel has a
pressure greater than 100 bar.
10. An insulative apparatus formed by the method of claim 1.
11. The insulative apparatus of claim 10, wherein the insulative
apparatus has a thermal conductivity of 16 mW/mK or less at a
pressure of 500 millibar or less.
12. An insulative apparatus comprising: a mold; a barrier material
connected to the mold; and a polyurethane foam inside the mold,
wherein the polyurethane foam is formed by injecting a polyurethane
foam composition into the mold and curing the polyurethane foam
composition, wherein the polyurethane foam composition includes a
polyol, an isocyanate, and supercritical carbon dioxide, and
wherein a vacuum is applied to the mold to provide pressure from 1
millibar to 500 millibar.
Description
FIELD
[0001] Embodiments relate to insulative apparatus, more
particularly, to insulative apparatus, and methods of forming the
same, that are formed from a polyurethane foam composition that
includes a polyol, an isocyanate, and supercritical carbon
dioxide.
BACKGROUND
[0002] Polyurethanes may be used in a variety of applications.
Depending upon an application, a particular property of a
polyurethane may be desired.
[0003] Polyurethane foams are used for a variety of applications.
For instance, polyurethane foams can be utilized in the appliance
industry, as well as the building industry, among others. For some
applications, polyurethane foams may be utilized to provide thermal
insulation, among other properties.
SUMMARY
[0004] The present disclosure provides methods of forming an
insulative apparatus, including: providing a barrier material to a
mold; injecting a polyurethane foam composition into the mold,
wherein the polyurethane foam composition includes a polyol, an
isocyanate, and supercritical carbon dioxide; curing the
polyurethane foam composition to form a polyurethane foam; and
applying a vacuum to the mold to provide a pressure from 1 millibar
to 500 millibar.
[0005] The present disclosure provides insulative apparatus
including: a mold; a barrier material connected to the mold; and a
polyurethane foam inside the mold, wherein the polyurethane foam is
formed by injecting a polyurethane foam composition into the mold
and curing the polyurethane foam composition, wherein the
polyurethane foam composition includes a polyol, an isocyanate, and
supercritical carbon dioxide, and wherein a vacuum is applied to
the mold to provide pressure from 1 millibar to 500 millibar.
[0006] The above summary of the present disclosure is not intended
to describe each disclosed embodiment or every implementation of
the present disclosure. The description that follows more
particularly exemplifies illustrative embodiments. In several
places throughout the application, guidance is provided through
lists of examples, which examples can be used in various
combinations. In each instance, the recited list serves only as a
representative group and should not be interpreted as an exclusive
list.
DETAILED DESCRIPTION
[0007] Insulative apparatus and methods of forming insulative
apparatus are described herein. As an example, a method of forming
an insulative apparatus can include providing a barrier material to
a mold; injecting a polyurethane foam composition into the mold,
wherein the polyurethane foam composition includes a polyol, an
isocyanate, and supercritical carbon dioxide; curing the
polyurethane foam composition to form a polyurethane foam; and
applying a vacuum to the mold to provide a pressure from 1 millibar
to 500 millibar. Advantageously, embodiments of the present
disclosure can provide improved thermal conductivity and/or
improved manufacturability, as compared to other insulating panels,
among other benefits.
[0008] Some previous insulating panels that utilize polyurethane
foam are manufactured at atmospheric pressures, i.e., the
polyurethane foam is in fluid communication with the environment
outside of the insulating panel. In other words, a fluid, e.g.,
air, may pass into and/or out of the insulating panel containing
the polyurethane foam. However, these previous insulating panels
can have a thermal conductivity of about 18 milliWatts/meter-degree
Kelvin [mW/(mK)] or higher, which may be an undesirable and/or
insufficient thermal conductivity for a number of applications.
[0009] Some other previous insulating panels that utilize
polyurethane foam can be referred to as vacuum insulation panels.
Vacuum insulation panels are manufactured at high vacuum, e.g.,
pressures of less than 1 millibar (mbar), and the polyurethane foam
generally has an average pore diameter of 200 micrometers (.mu.m)
or greater. Theses vacuum insulation panels are sealed at these
pressures such that the polyurethane foam is not in fluid
communication with the environment outside of the vacuum insulating
panel. In other words, a fluid, e.g., air, may not pass into and/or
out of the vacuum insulating panel containing the polyurethane
foam. Vacuum insulation panels can have a thermal conductivity of
about 5 mW/(mK) or lower. However, due to the high vacuum
associated with the vacuum insulation panels, manufacturing the
vacuum insulation panels can require particular equipment and/or
specialized manufacturing conditions, which can add to the cost to
the vacuum insulation panels and/or time for processing the vacuum
insulation panels. Additionally, due to the high vacuum associated
with the vacuum insulation panels, the shape of the vacuum
insulation panels may be restricted. For instance, it may be
difficult or even unrealizable to manufacture irregularly shaped
vacuum insulation panels, e.g., panels having sharp protrusions
and/or angles within the panel. As such, embodiments of the present
disclosure can provide improved manufacturability, as compared to
other insulating panels.
[0010] As mentioned, insulative apparatus and methods of forming
insulative apparatus are described herein. Embodiments of the
present disclosure provide an insulative apparatus having a thermal
conductivity from 8 mW/(mK) to 14 mW/(mK), which may be desirable
for a number of applications. All individual values and subranges
from 8 mW/(mK) to 14 mW/(mK) are included; for example, the
insulative apparatus can have a thermal conductivity from a lower
limit of 8 mW/(mK), 8.5 mW/(mK), 9 mW/(mK), or 9.5 mW/(mK) to an
upper limit of 14 mW/(mK), 13.5 mW/(mK), 13.25 mW/(mK), or 13
mW/(mK). This thermal conductivity can be achieved via a synergism
of the insulative apparatus components discussed further
herein.
[0011] Embodiments of the present disclosure provide insulative
apparatus that include a polyurethane foam. The polyurethane foam
can be formed from a polyurethane foam composition. Polyurethanes
are polymers including chains of units joined by carbamate links,
which may be referred to as urethane links. Polyurethanes can be
formed by reacting isocyanates with polyols in the presence of a
blowing agent. As used herein, "polyol" refers to a molecule having
an average of greater than 1.0 hydroxyl groups per molecule. Foams
are dispersions in which a gas is dispersed in a liquid material, a
solid material, and/or a gel material.
[0012] Embodiments of the present disclosure provide that the
polyurethane foam composition can include a polyol. Various polyols
may be utilized. Examples of polyols include, but are not limited
to a polyester-polyols, poiyether-poiyols, and combinations
thereof.
[0013] Polyester-polyols may be prepared from, for example, organic
dicarboxylic acids having from 2 to 12 carbon atoms, including
aromatic dicarboxylic acids having from 8 to 12 carbon atoms and
polyhydric alcohols, including diols having from 2 to 12 carbon
atoms. Examples of suitable dicarboxylic acids are succinic acid,
glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic
acid, decanedicarboxylic acid, maleic acid, fumaric acid, phthalic
acid, isophthalic acid, terephthalic acid, and the isomeric
naphthalene-dicarboxylic acids. The dicarboxylic acids may be used
either individually or mixed with one another. Free dicarboxylic
acids may be replaced by a corresponding dicarboxylic acid
derivative, for example, dicarboxylic esters of alcohols having 1
to 4 carbon atoms or dicarboxylic anhydrides. Some particular
examples may utilize dicarboxylic acid mixtures including succinic
acid, glutaric acid and adipic acid in ratios of, for instance,
from 20 to 35:35 to 50:20 to 32 parts by weight, and adipic acid,
and mixtures of phthalic acid and/or phthalic anhydride and adipic
acid, mixtures of phthalic acid or phthalic anhydride, isophthalic
acid and adipic acid or dicarboxylic acid mixtures of succinic
acid, glutaric acid and adipic acid and mixtures of terephthalic
acid and adipic acid or dicarboxylic acid mixtures of succinic
acid, glutaric acid and adipic acid. Examples of dihydric and
polyhydric alcohols are ethanediol, diethylene glycol, 1,2- and
1,3-propanediol, dipropylene glycol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, glycerol,
trimethylolpropane, among others. Some particular examples provide
that ethanediol, diethylene glycol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol or mixtures of at least two of said
diols, in particular mixtures of 1,4-butanediol, 1,5-pentanediol
and 1,6-hexanediol. Furthermore, polyester-polyols made from
lactones, e.g., .epsilon.-caprolactone or hydroxycarboxylic acids,
e.g., to .omega.-hydroxycaproic acid and hydrobenzoic acid, may
also be employed.
[0014] Some embodiments of the present disclosure provide that
polyester-polyols may be prepared by polycondensing the organic,
e.g., aliphatic and preferably aromatic polycarboxylic acids and
mixtures of aromatic and aliphatic polycarboxylic acids, and/or
derivatives thereof, and polyhydric alcohols without using a
catalyst or in the presence of an esterification catalyst, in an
inert gas atmosphere, e.g., nitrogen, carbon monoxide, helium,
argon, inter alia, in the melt at from about 150 to about
250.degree. C., at atmospheric pressure or under reduced pressure
until a desired acid number, which can be less than 10, and in some
instances preferably less than 2, is reached. Some embodiments of
the present disclosure provide that the esterification mixture is
polycondensed at the above mentioned temperatures under atmospheric
pressure and subsequently under a pressure of less than 500
millibar, e.g., from 50 to 150 mbar, until an acid number of from
80 to 30, e.g., from 40 to 30, has been reached. Examples of
suitable esterification catalysts include, but are not limited to,
iron, cadmium, cobalt, lead, zinc, antimony, magnesium, titanium
and tin catalysts in the form of metals, metal oxides or metal
salts. Polycondensation may also be carried out in a liquid phase
in the presence of diluents and/or entrainers, e.g., benzene,
toluene, xylene or chlorobenzene, for removal of the water of
condensation by azeotropic distillation, for instance.
[0015] Polyester-polyols can be prepared by polycondensing organic
polycarboxylic acids and/or derivatives thereof with polyhydric
alcohols in a molar ratio of from 1:1 to 1:1.8, e.g., from 1:1.05
to 1:1.2, for instance.
[0016] Also, anionic polymerization may be utilized. For instance,
alkali metal hydroxides such as sodium hydroxide or potassium
hydroxide, or alkali metal alkoxides, such as sodium methoxide,
sodium ethoxide, potassium ethoxide or potassium isopropoxide as
catalyst and with addition of at least one initiator molecule
containing from 2 to 8 reactive hydrogen atoms in bound form or by
cationic polymerization using Lewis acids, such as antimony
pentachloride, boron fluoride etherate, inter alia, or bleaching
earth as catalysts, from one or more alkylene oxides having from 2
to 4 carbon atoms in the alkylene moiety may be utilized.
[0017] Examples of suitable alkylene oxides include, but are not
limited to, tetrahydrofuran, 1,3-propylene oxide, 1,2- and
2,3-butylene oxide, styrene oxide and preferably ethylene oxide and
1,2-propylene oxide. The alkylene oxides may be used individually,
alternatively one after the other, or as mixtures. Examples of
suitable initiator molecules include, but are not limited to,
water, organic dicarboxylic acids such as succinic acid, adipic
acid, phthalic acid and terephthalic acid, and a variety of amines,
including but not limited to aliphatic and aromatic, unsubstituted
or N-mono-, N,N- and N,N'-dialkyl-substituted diamines having from
1 to 4 carbon atoms in the alkyl moiety, such as unsubstituted or
mono- or dialkyl-substituted ethylenediamine, diethylenetriamine,
triethylenetetramine, 1,3-propylene-diamine, 1,3- and 1,4-butylene
diamine, 1,2-, 1,3-, 1,4-, 1,5- and 1,6-hexamethylenediamine,
aniline, cyclohexanediamine, phenylenediamines, 2,3-, 2,4-, 3,4-
and 2,6-tolylenediamine and 4,4'-, 2,4'- and
2,2'-diaminodiphenylmethane. Other suitable initiator molecules
include alkanolamines, e.g., ethanolamine, N-methyl- and
N-ethylethanolamine, dialkanolamines, e.g., diethanolamine,
N-methyl- and N-ethyldiethanolamine, and trialkanolamines, e.g.,
triethanolamine, and ammonia, and polyhydric alcohols, in
particular dihydric and/or trihydric alcohols, such as ethanediol,
1,2- and 1,3-propanediol, diethylene glycol, dipropylene glycol,
1,4-butanediol, 1,6-hexanediol, glycerol, trimethylolpropane,
pentaerythritol, sorbitol and sucrose, polyhydric phenols, for
example, 4,4'-dihydroxydiphenylmethane and
4,4'-dihydroxy-2,2-diphenylpropane, resols, for example, oligomeric
products of the condensation of phenol and formaldehyde, and
Mannich condensates of phenols, formaldehyde and dialkanolamines,
and melamine.
[0018] One or more embodiments of the present disclosure provide
that the polyol can include polyether-polyols prepared by anionic
polyaddition of at least one alkylene oxide, e.g., ethylene oxide
or 1,2-propylene oxide or 1,2-propylene oxide and ethylene oxide,
onto, as initiator molecule, at least one aromatic compound
containing at least two reactive hydrogen atoms and containing at
least one hydroxyl, amino and/or carboxyl group. Examples of
initiator molecules include aromatic polycarboxylic acids, for
example, hemimellitic acid, trimellitic acid, trimesic acid and
preferably phthalic acid, isophthalic acid and terephthalic acid,
or mixtures of at least two polycarboxylic acids, hydroxycarboxylic
acids, for example, salicylic acid, p- and m-hydroxybenzoic acid
and gallic acid, aminocarboxylic acids, for example, anthranilic
acid, m- and p-aminobenzoic acid, polyphenols, for example,
resorcinol, and according to one or more embodiments of the present
disclosure, dihydroxydiphenylmethanes and
dihydroxy-2,2-diphenylpropanes, Mannich condensates of phenols,
formaldehyde and dialkanolamines, preferably diethanolamine, and
aromatic polyamines, for example, 1,2-, 1,3- and
1,4-phenylenediamine, e.g., 2,3-, 2,4-, 3,4- and
2,6-tolylenediamine, 4,4'-, 2,4'- and 2,2'-diaminodiphenylmethane,
polyphenyl-polymethylene-polyamines, mixtures of
diaminodiphenylmethanes and polyphenyl-polymethylene-polyamines, as
formed, for example, by condensation of aniline with formaldehyde,
and mixtures of at least two polyamines.
[0019] Examples of hydroxyl-containing polyacetals include
compounds which may be prepared from glycols, such as diethylene
glycol, triethylene glycol,
4,4'-dihydroxyethoxydiphenyldimethylmethane, hexanediol and
formaldehyde. Suitable polyacetals can also be prepared by
polymerizing cyclic acetals.
[0020] Examples of hydroxyl-containing polycarbonates can be
prepared, for example, by reacting diols, such as 1,3-propanediol,
1,4-butanediol and/or 1,6-hexanediol, diethylene glycol,
triethylene glycol or tetraethylene glycol, with diaryl carbonates,
e.g., diphenyl carbonate, or phosgene.
[0021] As discussed herein, the polyol may be referred to as a
formulated polyol. A formulated polyol may be a mixture, e.g., a
blend, of a number of polyols and/or additives discussed herein.
For example, a formulated polyol can include a number of blowing
agents, catalysts, fillers, flame retardants, chain extenders or
cross-linkers, colorants and/or combinations thereof, among
others.
[0022] Examples of commercially available polyols include, but are
not limited to, polyols sold under the trade name VORANOL.TM.,
TERCAROL.TM., and VORATEC.TM., among others. Embodiments of the
present disclosure provide that the polyurethane foam composition
can include an isocyanate. Various isocyantaes, e.g.,
polyisocyantes, may be utilized. As used herein, "polyisocyanate"
refers to a molecule having an average of greater than 1.0
isocyanate groups per molecule, e.g. an average functionality of
greater than 1.0. A number of embodiments of the present disclosure
provide that the isocyanate can have a functionality of 3 or
greater.
[0023] The polyisocyanate can include an aliphatic polyisocyanate,
a cycloaliphatic polyisocyanate, an araliphatic polyisocyanate, an
aromatic polyisocyanate, or combinations thereof. Examples of
polyisocyanates include, but are not limited to, alkylene
diisocyanates such as 1,12-dodecane diisocyanate;
2-ethyltetramethylene 1,4-diisocyanate; 2-methyl-pentamethylene
1,5-diisocyanate; 2-ethyl-2-butylpentamethylene 1,5-diisocyanate;
tetramethylene 1,4-diisocyanate; and hexamethylene
1,6-diisocyanate. Examples of polyisocyanates include, but are not
limited to cycloaliphatic diisocyanates, such as cyclohexane 1,3-
and 1,4-diisocyanate and mixtures of these isomers;
1-isocyanato-3,3,5-trimethyl-5-isocyanato-methylcyclohexane; 2,4-
and 2,6-hexahydrotolylene diisocyanate; and the corresponding
isomer mixtures, 4,4-, 2,2'- and 2,4'-dicyclohexylmethane
diisocyanate; and corresponding isomer mixtures. Examples of
polyisocyanates include, but are not limited to, araliphatic
diisocyanates, such as 1,4-xylylene diisocyanate and xylylene
diisocyanate isomer mixtures. Examples of polyisocyanates include,
but are not limited to, aromatic polyisocyanates, e.g., 2,4- and
2,6-tolylene diisocyanate and the corresponding isomer mixtures,
4,4'-, 2,4'- and 2,2'-diphenylmethane diisocyanate and the
corresponding isomer mixtures, mixtures of 4,4'- and
2,4'-diphenylmethane diisocyanates, polyphenyl-polymethylene
polyisocyanates, mixtures of 4,4'-, 2,4'- and 2,2'-diphenylmethane
diisocyanates and polyphenyl-polymethylene polyisocyanates (crude
MDI), and mixtures of crude MDI and tolylene diisocyanates. The
polyisocyanate may be employed individually or as combinations
thereof.
[0024] One or more embodiments of the present disclosure provide
that a modified polyisocyanate may be used utilized. Examples of
modified polyisocyanates include, but are not limited, to ester-,
urea-, biuret-, allophanate-, uretoneimine-, carbodiimide-,
isocyanurate-, uretdione- and/or urethane-containing
polyisocyanates. Examples include 4,4'-diphenylmethane
diisocyanate, 4,4'- and 2,4'-diphenylmethane diisocyanate mixtures,
or crude MDI or 2,4- or 2,6-tolylene diisocyanate, in each case
modified by low molecular weight diols, triols, dialkylene glycols,
trialkylene glycols or polyoxyalkylene glycols having molecular
weight of up to about 6,000. Specific examples of di- and
polyoxyalkylene glycols, which may be employed individually or as
mixtures, include diethylene, dipropylene, polyoxyethylene,
polyoxypropylene and polyoxy-propylene-polyoxyethylene glycols,
triols and/or tetrols. NCO-containing prepolymers containing from
25 to 3.5 percent by weight, e.g., from 21 to 14 percent by weight,
of NCO, based on the total weight, and prepared from the polyester-
and/or preferably polyether-polyols described herein, and
4,4'-diphenylmethane diisocyanate, mixtures of 2,4'- and
4,4'-diphenylmethane diisocyanate, 2,4- and/or 2,6-tolylene
diisocyanates or crude MDI are also suitable. Furthermore, liquid
polyisocyanates containing carbodiimide groups and/or isocyanurate
rings and containing from 33.6 to 15 percent by weight, e.g., from
31 to 21 percent by weight, of NCO, based on the total weight,
e.g., based on 4,4'-, 2,4'- and/or 2,2'-diphenylmethane
diisocyanate and/or 2,4' and/or 2,6-tolylene diisocyanate, may also
be utilized. Modified polyisocyanates may be mixed with one another
or with unmodified organic polyisocyanates, e.g., 2,4'- or
4,4'-diphenylmethane diisocyanate, crude MDI, and/or 2,4- and/or
2,6-tolylene diisocyanate. A number of embodiments of the present
disclosure provide that the isocyanate includes a polymeric
isocyanate, such as isocyanic acid polymethylenepolyphenylene ester
(PMDI), among others.
[0025] The polyisocyanate may be prepared, e.g., by a known
process. For instance, the polyisocyanate can be prepared by
phosgenation of corresponding polyamines with formation of
polycarbamoyl chlorides and thermolysis thereof to provide the
polyisocyanate and hydrogen chloride, or by a phosgene-free
process, such as by reacting the corresponding polyamines with urea
and alcohol to give polycarbamates, and thermolysis thereof to give
the polyisocyanate and alcohol, for example.
[0026] The polyisocyanate may be obtained commercially. Examples of
commercial polyisocyanates include, but are not limited to,
polyisocyanates sold under the trade names PAPI.TM. and
VORATEC.TM., such as VORATEC.TM. SD100, a polymeric methylene
diphenyl diisocyanate (MDI) available from The Dow Chemical
Company, among others.
[0027] Embodiments of the present disclosure provide that the
polyurethane foam composition can have an isocyanate index from 70
to 500. All individual values and subranges from 70 to 500 are
included; for example, the polyurethane foam composition can have
an isocyanate index from a lower limit of 70, 80, 90, or 100 to an
upper limit of 500, 250, 150, or 130.
[0028] Embodiments of the present disclosure provide that the
polyurethane foam composition includes supercritical carbon
dioxide. The supercritical carbon dioxide, which may be referred to
as a blowing agent, may be utilized to help foam formation of the
polyurethane foam composition. Advantageously, utilizing the
supercritical carbon dioxide can help provide that the polyurethane
foam has a number of desirable properties, as discussed further
herein, which may help to provide the thermal conductivity
discussed herein.
[0029] The supercritical carbon dioxide can be from 2 to 25 parts
by weight of the polyurethane foam composition, based on 100 parts
of the polyol utilized. All individual values and subranges from 2
to 25 parts by weight are included; for example, the supercritical
carbon dioxide can be from a lower limit of 2, 5, or 8 parts by
weight to an upper limit of 25, 23, or 20 parts by weight based on
100 parts of the polyol utilized.
[0030] One or more embodiments of the present disclosure provide
that the polyurethane foam composition can include a surfactant. As
used herein, a surfactant may also be utilized as a cell opener.
Examples of surfactants include silicon-based compounds such as
silicone oils and organosilicone-polyether copolymers, such as
polydimethyl siloxane and polydimethylsiloxane-polyoxyalkylene
block copolymers, e.g., polyether modified polydimethyl siloxane,
and combinations thereof. Examples of surfactants include silica
particles and silica aerogel powders, as well as organic
surfactants such as nonylphenol ethoxylates and VORASURF.TM. 504,
which is an ethylene oxide/butylene oxide block co-polymer having a
relatively high molecular weight, and combinations thereof, among
others. Surfactants are available commercially and include those
available under trade names such as DABCO.TM., NIAX.TM., and
TEGOSTAB.TM., among others. Commercially available surfactants
include those available from Dearmate and Momentive, among other
suppliers. One or more embodiments of the present disclosure
provide that the surfactant, when utilized, is from 0.1 percent to
10 percent of a total weight of the polyol utilized. All individual
values and subranges from 0.1 percent to 10 percent are included;
for example, the surfactant can be from a lower limit of 0.1, 0.2,
or 0.3 percent to an upper limit of 10, 8.5, or 6.0 percent of a
total weight of the polyol utilized.
[0031] One or more embodiments of the present disclosure provides
that the polyurethane foam composition can include a catalyst,
e.g., a blowing catalyst, a gel catalyst, a trimerization catalyst,
or a combination thereof, among others. A used herein, blowing
catalysts and gel catalysts, may be differentiated by a tendency to
favor either the urea (blow) reaction, in the case of the blowing
catalyst, or the urethane (gel) reaction, in the case of the gel
catalyst. A trimerization catalyst may be utilized to promote
reactivity of the polyurethane foam composition.
[0032] Examples of blowing catalysts, e.g., catalyst that can tend
to favor the blow reaction include, but are not limited to, short
chain tertiary amines or tertiary amines containing an oxygen. For
instance, blowing catalysts include
bis-(2-dimethylaminoethyl)ether; pentamethyldiethylene-triamine,
triethylamine, tributyl amine, N,N-dimethylaminopropylamine,
dimethylethanolamine, N,N,N',N'-tetra-methylethylenediamine, and
combinations thereof, among others.
[0033] Examples of gel catalysts, e.g., catalyst that can tend to
favor the gel reaction, include, but are not limited to,
organometallic compounds, cyclic tertiary amines and/or long chain
amines, e.g., that contain several nitrogen atoms, and combinations
thereof. Organometallic compounds include organotin compounds, such
as tin(II) salts of organic carboxylic acids, e.g., tin(II)
diacetate, tin(II) dioctanoate, tin(II) diethylhexanoate, and
tin(II) dilaurate, and dialkyltin(IV) salts of organic carboxylic
acids, e.g., dibutyltin diacetate, dibutyltin dilaurate, dibutyltin
maleate and dioctyltin diacetate. Bismuth salts of organic
carboxylic acids may also be utilized as the gel catalyst, such as,
for example, bismuth octanoate. Cyclic tertiary amines and/or long
chain amines include dimethylbenzylamine,
N,N,N',N'-tetramethylbutanediamine, dimethylcyclohexylamine,
triethylenediamine, and combinations thereof, and combinations
thereof.
[0034] Examples of trimerization catalysts include
tris(dialkylaminoalkyl)-s-hexahydrotriazines, such as
1,3,5-tris(N,N-dimethylaminopropyl)-s-hexahydrotriazine;
[2,4,6-Tris (dimethylaminomethyl) phenol]; potassium acetate,
potassium octoate; tetraalkylammonium hydroxides such as
tetramethylammonium hydroxide; alkali metal hydroxides such as
sodium hydroxide; alkali metal alkoxides such as sodium methoxide
and potassium isopropoxide; and alkali metal salts of long-chain
fatty acids having 10 to 20 carbon atoms and, combinations thereof.
Some commercially available trimerization catalysts include
DABCO.RTM. TMR-30, DABCO.RTM. K 2097; DABCO.RTM. K15, POLYCAT.RTM.
5, POLYCAT.RTM. 8, POLYCAT.RTM. 41, POLYCAT.RTM. 43, POLYCAT.RTM.
46, DABCO.RTM. TMR, CURITHANE 52, among others.
[0035] The catalyst can be utilized from 0.5 percent to 5.0 percent
of a total weight of the polyol utilized. All individual values and
subranges from 0.5 percent to 5.0 percent are included; for
example, the catalyst can be from a lower limit of 0.5, 0.6, or 0.7
percent to an upper limit of 5.0, 4.0, or 3.0 percent of the total
weight of the polyol utilized.
[0036] One or more embodiments of the present disclosure provide
that the polyurethane foam composition can include one or more
additional components. Different additional components and/or
different amounts of the additional components may be utilized for
various applications. Examples of additional components include
pigments, colorants, flame retardants, crosslinkers, chain
extenders, antioxidants, bioretardant agents, and combinations
thereof, among others. One or more embodiments of the present
disclosure provide that the polyurethane foam composition can
include an opacifer. An example of an opacifer is carbon black.
[0037] As mentioned, the polyurethane foam composition can be
injected into the mold, e.g., a cavity. Embodiments of the present
disclosure provide that the mold may have various shapes and/or
sizes. One or more embodiments of the present disclosure provide
that the mold is suitable for refrigeration applications, e.g.,
insulation. Advantageously, the mold may be irregularly shaped
and/or have a number of sharp protrusions and/or angles within the
mold, in contrast to vacuum insulation panels.
[0038] Embodiments of the present disclosure include a barrier
material. The barrier material can help reduce flow of a fluid into
and/or out of the mold, e.g., after the polyurethane foam has cured
within the mold. The barrier material can be sealed to help
maintain a desired pressure within the mold, as discussed further
herein. The barrier material can have an oxygen transmission rate
from 1e-20 m.sup.3 m/(m.sup.2 Pa day) to 1e-12_m.sup.3 m/(m.sup.2
Pa day). All individual values and subranges from 1e-20 m.sup.3
m/(m.sup.2 Pa day) to 1e-12_m.sup.3 m/(m.sup.2 Pa day) are
included; for example, the barrier material can have an oxygen
transmission rate from an upper limit of 1e-12, 1e-13, or 1e-14
m.sup.3 m/(m.sup.2 Pa day) to a lower limit of 1e-20, 1e-19, or
1e-18 m.sup.3 m/(m.sup.2 Pa day).
[0039] In addition, the barrier material can have a water vapor
transmission rate from 1e-15 m.sup.3 m/(m.sup.2 Pa day) to
1e-10_m.sup.3 m/(m.sup.2 Pa day). All individual values and
subranges from 1e-15 m.sup.3 m/(m.sup.2 Pa day) to 1e-10_m.sup.3
m/(m.sup.2 Pa day) are included; for example, the barrier material
can have a water vapor transmission rate from a lower limit of
1e-15, or 1e-15 m.sup.3 m/(m.sup.2 Pa day) to an upper limit of
1e-10, or 1e-11 m.sup.3 m/(m.sup.2 Pa day). Examples of barrier
materials include those available under the trade name SARANEX.TM.,
among others.
[0040] The barrier material can be connected to the mold, e.g., the
barrier material can be secured to the mold via chemical adhesion,
mechanical adhesion, material support, and combinations thereof.
The barrier material can be located inside the mold and/or outside
the mold. One or more embodiments of the present disclosure provide
that barrier material may be injected into the mold. For instance,
fluid may be injected into the mold, which cures to form the
barrier material within the mold.
[0041] A number of components of the polyurethane foam composition
may be combined, e.g., mixed, prior to being injected into the
mold. A number components of the polyurethane foam composition may
be uncombined with other components of the polyurethane foam
composition prior to being injected into the mold. In other words,
all components of the polyurethane foam composition are not
required to be combined with one another prior to being injected
into the mold.
[0042] One or more embodiments of the present disclosure provide
that a number of components of the polyurethane foam composition,
e.g., polyols, supercritical carbon dioxide, and/or surfactants,
among others, may be combined prior to being injected into the
mold. This combination may be referred to as a "B" side, which in
Europe may be referred to as the "A" side. As the carbon dioxide is
in the supercritical state, the number of components may be
combined in a vessel that is suitable to maintain a temperature and
pressure at which the carbon dioxide can remain in the
supercritical state.
[0043] One or more embodiments of the present disclosure provide
that a number of components of the polyurethane foam composition,
e.g., polyisocyanates, can be included in an "A" side, which in
Europe may be referred to as the "B" side. The A side and the B
side can be combined to provide the isocyanate index discussed
herein.
[0044] One or more embodiments of the present disclosure provide
that the A side and the B side can be combined, e.g., with an
injection head, and then, more or less simultaneously, be injected
into the mold to be filled. One or more embodiments of the present
disclosure provide that reaction injection molding may be
utilized.
[0045] As the component of the polyurethane foam composition are
injected into the mold, foaming and polymerization occurs to form a
polyurethane foam. The foaming and/or polymerization can continue
until the mold is filled with the polyurethane foam.
[0046] As mentioned, the porosity from has a number of desirable
properties, which may help to provide the thermal conductivity
discussed herein. For instance, utilizing the supercritical carbon
dioxide, in contrast to other blowing agents, can help provide that
the polyurethane foam has an average pore diameter from 1 micron to
100 microns. All individual values and subranges from 1 micron to
100 microns are included; for example, the polyurethane foam can
have an average pore diameter from a lower limit of 1 micron, 2
microns, 2.5 microns, 3 microns, or 3.5 microns to an upper limit
of 100 microns, 75 microns, 50 microns, 35 microns, or 25 microns.
One or more embodiments of the present disclosure provide that the
average pore diameter has a coefficient of variation not greater
than 25% For instance, the average pore diameter can have a
coefficient of variation 25% or less, 20% or less. 15% or less, or
10% or less.
[0047] Embodiments of the present disclosure provide that the
polyurethane foam can be an open cell foam. The open cells may be
referred to as intercommunicating. The polyurethane foam can have
an open cell percentage of 90% or greater, e.g., an open cell
percentage from 90% to 100%. For example, the polyurethane foam can
have an open cell percentage from a lower limit of 90%, 95%, 96%,
or 97% to an upper limit of 100%, 99.85%, 99.75% or 99.5%.
[0048] Embodiments of the present disclosure provide that the
polyurethane foam can have a porosity from 80% to 98%. All
individual values and subranges from 80% to 98% are included; for
example, the polyurethane foam can have a porosity from a lower
limit of 80%, 82.5%, or 85% to an upper limit of 98%, 97%, or
95%.
[0049] Embodiments of the present disclosure provide that a vacuum
may be applied to the mold to provide a pressure from 1 millibar to
500 millibar. All individual values and subranges from 1 millibar
to 500 millibar are included; for example, the vacuum may be
applied to the mold to provide a pressure from a lower limit of 1
millibar, 5 millibar, 10 millibar, or 50 millibar to an upper limit
of 500 millibar, 450 millibar, 400 millibar, or 350 millibar. The
vacuum may be applied after the curing of the polyurethane foam
composition within the mold to provide a desired pressure within
the mold.
[0050] The insulative apparatus as disclosed herein can be formed
by applying the vacuum to the mold having the polyurethane foam
therein and thereafter sealing the barrier material. The pressure
within the mold, which is achieved by application of the vacuum,
can be maintained by the sealed barrier material, e.g., for an
operational lifetime of the insulative apparatus. The insulative
apparatus disclosed herein can be utilized for a variety of
applications, such as in appliance insulating walls for uses such
as, refrigerators, freezers, and hot water storage tanks, as well
as building applications, among others.
[0051] Application of the vacuum can provide that fluid within the
sealed mold, i.e. fluid within the insulative apparatus such as
carbon dioxide, can have a Knudsen number from 0.85 to 1.15. All
individual values and subranges from 0.85 to 1.15 are included; for
example, fluid within the sealed mold can have a Knudsen number
from a lower limit of 0.85, 0.90, or 0.95 to an upper limit of
1.15, 1.00, or 1.05.
[0052] As mentioned, the insulative apparatus components, e.g., the
polyurethane foam and the pressure achieved by the vacuum
application, can advantageously provide a synergism to achieve the
thermal conductivity discussed herein.
Examples
[0053] In the Examples, various terms and designations for
materials are used including, for instance, the materials included
in Table 1. For Table 1, F indicates the functionality and OH no
indicates the hydroxyl number.
TABLE-US-00001 TABLE 1 Material Trade Name Material
characteristic(s) Material supplier Polyol VORANOL .TM. F = 6; OH
n.sup.o 482, PO based The Dow Chemical RN 482 Company (TDCC) (RN
482) Polyol VORANOL .TM. F = 4.5; OH n.sup.o 640, PO based TDCC RN
490 (RN 490) Polyol TERCAROL F = 4; OH n.sup.o 440, PO based TDCC
5903 (T 5903) Polyol VORATEC .TM. F = 3; OH n.sup.o 160, PO based
TDCC SD301 (SD 301) Polyol VORANOL .TM. F = 3, OH n.sup.o 650, PO
based TDCC CP 260 (CP 260) Polyol VORANOL .TM. F = 4.9, OH n.sup.o
360, PO based TDCC RH 360 (RH 360) Polyol VORANOL .TM. F = 3, OH
n.sup.o 370, PO based TDCC CP 450 (CP 450) Catalyst POLYCAT .RTM.-5
N,N,N,N,N-Pentamethyldiethylenetria Air product (PC-5) Catalyst
POLYCAT .RTM.-8 N,N-Dimethylcyclohexylamine Air product (PC-8)
Catalyst POLYCAT .RTM.- Dimethylaminopropyl- Air product 41
hexahydrotriazine,N,N',N'' (PC-41) Surfactant AK 8850 Silicone
surfactant Dearmate Surfactant L 6164 Silicone surfactant Momentive
Surfactant L 6165 Silicone surfactant Momentive Cell opener TEGO
.TM.-501 Silicone surfactant Evonik Cell opener AK 9903 Silicone
surfactant Dearmate Isocyanate VORATEC .TM. PMDI TDCC SD 100
Isocyanate PAPI .TM.-135C PMDI TDCC Carbon Dioxide Air product
Barrier Material SARANEX .TM. TDCC indicates data missing or
illegible when filed
[0054] Example 1, a method of forming an insulative apparatus, was
performed as follows. Polyol A [SD301 (47.55 grams), CP260 (38
grams), T5903 (9.5 grams)], catalyst [PC-41 (0.57 grams), PC-5
(0.48 grams), PC-8 (1.9 grams)] and surfactant L 6164 (2 grams)
were added to a pressure reactor (100 ml Pan reactor) that was
maintained at 10 MPa and 40.degree. C. thereafter. Supercritical
carbon dioxide was injected into the pressure reactor to saturation
of the contents of the pressure reactor. The temperature and the
pressure inside the pressure reactor were maintained for 30 minutes
to facilitate the carbon dioxide saturation while the contents of
the pressure reactor were stirred. A high pressure homogenizer was
used to form an emulsion with the contents of the pressure reactor;
the emulsion had droplets with diameters ranging from approximately
5 nanometers to approximately 300 nanometers. A polyurethane foam
composition was formed when PAPI.TM.-135C isocyanate (101 grams)
was added to the pressure reactor and the contents of the pressure
reactor were stirred for approximately 1 minute. After
approximately 8 minutes, the polyurethane foam composition, having
a viscosity of approximately 0.5 Pa-s, was injected into a mold (20
cm.times.20 cm.times.2.5 cm) that was internally lined with a
barrier material (SARANEX.TM. NEX 23P). The polyurethane foam
composition cured to form a polyurethane foam completely filling
the mold cavity; a vacuum was applied to achieve a mold cavity
pressure of 10 millibar and the barrier material was sealed to
provide Example 2, an insulative apparatus.
[0055] Comparative Example A, a polyurethane foam, was formed with
components described in Table 2.
TABLE-US-00002 TABLE 2 Material Trade Name Weight (%) Polyol
VORANOL .TM. 27.54 RN 482 (RN 482) Polyol VORANOL .TM. 27.54 RN 490
(RN 490) Polyol TERCAROL 27.54 5903 (T 5903) Polyol VORATEC .TM.
9.18 SD301 (SD 301) Silicone surfactant TEGOSTAB .RTM. B 1.85 8523
Catalyst POLYCAT .RTM.-5 0.46 (PC-5) Catalyst POLYCAT .RTM.-8 1.37
(PC-8) Catalyst POLYCAT .RTM.- 0.65 41 (PC-41) Water 2.02 Cell
Opener TEGO .TM. 501 1.85 (Total Weight % 100.00 of formulated
polyol) Expansion agent HCFC-141B 12 (available from (based on
formulated Chemours) polyol) Isocyanate Papi-135C 147 (based on
formulated polyol)
[0056] Formulated polyol with composition shown above were added to
a container and mixed with an impeller at 3000 rpm for
approximately 1 minute; after which the contents of the container
were left to equilibrate for approximately 1 hour. Isocyanate with
composition shown above was added to the container and the contents
were mixed with an impeller at 3000 rpm for approximately 10
seconds. The contents of the container were poured into a mold (30
cm.times.20 cm.times.5 cm) and cured to form Comparative Example A.
Comparative Example A was cut (20 cm.times.20 cm.times.2.5 cm) and
thermal conductivity 23.degree. C. (ASTM E1225) was determined with
a EKO Heat Flow Meter (HC-074), a fixed lower plate temperature of
36.degree. C., and an upper plate temperature of 10.degree. C. For
Example 2 and Comparative Example A: average pore diameter was
determined by Scanning Electron Microscopy with Image Pro Plus
software; open cell percentage was determined by Micromeritics
Accupyc II 1340 according to ASTM D2856; and porosity was
determined by ASTM D792-00 involving weighing polymer foam in water
using a sinker; thermal conductivity was measured according to ISO
12939-01, using a heat flow meter instrument HC-074 by EKO
Instrument Trading Co., Ltd. The results are indicated in Table
3.
TABLE-US-00003 TABLE 3 Comparative Example 2 Example A Average pore
9 300 diameter (micrometers) Open cell percentage 95 98 Porosity 90
95 Mold cavity pressure 2 1013 (millibar) Thermal conductivity 13.0
32.0 (milliWatts/meter- degree Kelvin)
[0057] The data in Table 3 show that Example 2, has a desirable
thermal conductivity, as discussed herein. Additionally, Example 2
can advantageously provide improved manufacturability, as compared
to other insulating panels.
* * * * *